Research On Surrounding Rock Control Technology Of Roadway Driving Along Goaf Of Island Coal Face In Dongpang Coal Mine

In many coal mines in China,due to the frequent use of hopping and mining methods between mining areas,there is a common island working face.Due to the stress concentration in the working face of the island,the mine pressure appears to be more severe than the general working surface,and the compressive strength is higher than that of the conventional working surface.The surrounding rock support technology of the roadway is difficult to control the deformation of the surrounding rock of the roadway,which makes the roadway support difficult and affects the advancement speed of the working face.It is of great significance to use reasonable technology to solve the picking of the working face of the island,to improve the recovery rate of coal resources in the mining area,extend the service life of the mine and avoid waste of coal resources.The paper takes the track road of 21215 isolated working face of Dongpang Mine as the engineering background.Through theoretical analysis,combined with numerical simulation and verification,field industrial test and other methods,the deformation law of surrounding rock of roadway along the goaf is studied.The stress distribution characteristics in the coal pillar,the determination of the reasonable coal pillar width and the design optimization of the surrounding rock support parameters of the roadway.Through research,we mainly found the following rules:(1)The stress distribution characteristics of the island working face are obtained by numerical simulation.The vertical stress distribution from the middle of the working face to the edge of the coal pillar is symmetrically distributed,and the stress distribution is “saddle”.(2)The minimum reasonable coal pillar width of 6.58 m is obtained by theoretical calculation,and the influence law of coal pillar width on coal pillar stress distribution and coal pillar width on roadway surrounding rock during roadway excavation and working face mining are analyzed by numerical simulation.The influence law of deformation finally determined the reasonable coal pillar width of 7m.(3)The height of the unstable rock stratum is obtained by the peeping results of the surrounding rock of the roadway,and the length of the anchor support is calculated and determined.(4)Determine the length and load of the bolt by theoretical calculation,and according to the calculation results,the length of the bolt is 2.4m,the bolt type is BHRB400,and the high-strength left-handed non-longitudinal full-thread steel anchor is analyzed by numerical simulation.The influence of bolt length and spacing on the roadway support effect determines the support parameters and support form of the roadway.(5)Carrying out the industrial test of the surrounding rock control technology of the roadway,summarizing and analyzing the on-site mine pressure monitoring data,and observing the deformation of the surrounding rock of the roadway and the force monitoring of the anchor(cable)during the roadway excavation The surrounding rock deformation of the roadway is small,and the anchor(cable)is stable.The support technical scheme effectively controls the surrounding rock deformation of the roadway,improves the stability of the surrounding rock,and controls the deformation of the surrounding rock of the roadway.